SYNTHESIZER: Conver do{ }while(0) to non-loop block

[qinheping]

The following construct is common in C. It also appears in Kani compiled GOTO.

do {
  // loop body
} while (0)

However, the old contracts (non dfcc) doesn't support do/while loops. This PR as an ad hoc fix until we migrate the synthesizer to dfcc.

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[codecov]

Codecov Report

Patch coverage: 100.00% and project coverage change: -0.09 ⚠️

Comparison is base (0ca29d8) 78.55% compared to head (0f5e93e) 78.47%.

Additional details and impacted files

@@             Coverage Diff             @@
##           develop    #7744      +/-   ##
===========================================
- Coverage    78.55%   78.47%   -0.09%     
===========================================
  Files         1691     1691              
  Lines       193132   193136       +4     
===========================================
- Hits        151714   151559     -155     
- Misses       41418    41577     +159     

Impacted Files	Coverage Δ
...hesizer/enumerative_loop_contracts_synthesizer.cpp	96.27% <100.00%> (+0.07%)	⬆️

... and 13 files with indirect coverage changes

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